Locking shingle



F. J. WENDT LOCKING SHINGLE July 25, 1961 2 Sheets-Sheet 1 Filed June28, 1956 INVENTOR.

July 25, 1961 F. J. WENDT 2,993,307

LOCKING SHINGLE Filed June 28, 1956 2 Sheets-Sheet 2 IN V EN TOR.

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limited States Patent 2,993,307 4 LOOKING SHINGLE Frank J. Wendt,Chicago, 11L, assignor to United States Gypsum Company, Chicago, 111., acorporation of Illinois Filed June 28, 1956, Ser. No. 594,443 2 Claims.(CLEO-224) This invention relates to a locking shingle and moreparticularly to one with a novel type slot-tab interlock which affordsimproved resistance to tear and greater ease in insertion of the tabinto an appropriate slot during attachment of the shingle to a roof.

A popular type of roofing material now being sold in large quantitiesfor the covering of the sloping roof of houses is made by saturating afelt, usually formed from wood or rag fibers with asphalt, applying acoating of asphalt thereto and partially embedding colored granules intothe coating. Sheets of roofing material formed in this manner are soldin roll, strip or individual form. This invention is concerned withthose sold in strip form, particularly those known as thick-butt orsquare-butt asphalt shingles. These shingles are formed by cuttingtransverse slots or cut-outs part way in from the exposed or lower edgeof the strip as far back as the shingle is to be exposed to form shinglesimulating units which when applied to a roof give a pleasing shingledefiect. The exposed part is referred to as the butt" portion, thatremaining and which is covered, the head portion. When these shinglesare subjected to a wind of high velocity upon a pitched roof the exposedportion has a tendency to fold over and sometimes tear 011. This notonly gives a very displeasing appearance but also may result in a roofleak.

A great number of means have been tried to overcome the tendency of theexposed or butt portion to blow oil under high wind velocity. Some ofthese are: cementing the butt portion down with a waterproof adhesivesuch as asphalt; stapling it to the course below; securing the bottomexposed edge to the course below by a clip extending around the bottomedge of each shingle unit; and locking the butt to the shingle below bymeans of a tab.

This invention relates to an improvement in the method of using tabs forlocking the lower butt edge of the shingles in each course to theshingle immediately underneath. Many ways of effecting this locking havebeen set forth by the prior art and while such locking has improved thewind resistance of the exposed portions of the shingles, the tabs havebeen difficult to apply and they have been occasionally torn ordisengaged due in part to the manner in which the shingles are raised bythe wind when it blows from certain directions. Accordingly, it is anobject of the invention to provide an improved locking tab by means ofwhich the resistance to tear is increased coupled with an improvement inmeans for interlocking the parts of the shingles.

It is another object of this invention to provide a novel type of taband slot combination for locking the butt portion of strip shingles tothe shingles of the course underneath.

It is also an object of this invention to provide a means of lockingdown the butts of shingles which is easy to engage.

It is a further object of this invention to provide means of lockingdown shingles in which the locking tabs are stressed under high windvelocity in a novel manner tending to reduce the danger of tear.

It is a still further object of this invention to provide means forlocking the exposed horizontal edge of strip shingles so that they willraise with the wind and orient 2,9d3,3d7 Patented July 25, 1961 dangerof tear but still permit them to return to their original position afterthe wind has subsided.

It is' a further object of the invention to provide an improved roofconstruction utilizing shingles interlocked in a novel manner.

This invention may be further understood by reference to the drawings,in which FIGURE 1 is a view of a portion of a roof according to theinvention showing the shingles in place and the tabs concealed;

FIG. 2 is a top view of a slot-tab shingle made according to theinvention;

FIG. 3 is a view similar to FIG. 1, illustrating the position of a stripshingle as the tabs are about to be inserted into the slots, and

FIG. 4 shows the relative position of the tab and slot in a lockedposition when subjected to a high wind velocity.

Referring to the drawings, there is shown in FIG. 1 a roof construction10 utilizing a series of shingle strips 11 according to the invention.Such shingle strips may be formed by cutting into the form shown in FIG.2

from flexible asphalt roofing made by applying granules to an asphaltcoating over asphalt saturated paper or rag felt. In the figures, theshingle strips 11 are shown as comprising a head portion 12 and a buttportion formed into two shingle-simulating units 13 and 14 by the cutout15 extending inwardly and upwardly from the exposed edge. Two of theseshingle-simulating units are usually in each shingle strip which issometimes referred to as the square-butt type. The shingle simulatingunit 13 is provided with a cut-out portion 27 of the same themselvesthereto in a manner which will decrease .the

extent as cut-out 15 so that when the shingle strips are placed side byside, the appearance of individual shingles is achieved.

A slot 16 is cut into unit 13 inwardly from one edge of cut-out 15, anda slot 17 is cut into unit 14 as shown. The shingle unit 13 has aportion thereof extending beyond its lower horizontal or exposed edge,substantially medially situated, and referred to as the tab element 18.

Similarly, a tab 19 extends downwardly from shingle unit 14. The loweredges of the tabs may terminate in horizontal lines which aresubstantially parallel with the lower edge of the butts, or they may beinclined.

The tab 18 or locking segment upon the side facing away from slot 15 hasa wide-mouthed or wedge-shaped recess 21 extending inwardly to form athroat 22 connecting the tab to the butt portion 13. The recess 21 isbounded above by the lower exposed edge 23 of the butt portion 13 andbelow by the upper edge of the tab which is inclined upwardly andinwardly to the throat. The lower edge of the recess is not continuous,for that near the outer edge of the tab extends upwardly towards butspaced fiom the exposed edge to form the lock or toe section 24. Thissection terminates abruptly in a hook edge 25 substantiallyright-angularly disposed (in the form shown) to the inclined lower edgeof the recess. The toe section is an important part of the invention andis spaced a considerable distance from the throat portion so as to leavea large part of the lower or inclined boundmy of the recess 21unaltered. The up per edge of the toe section may be inclined parallelto the lower edge referred to above or it may be at a different angle.In any case sufiicient space must be provided between the lower edge ofthe butt and the upper edge of the toe so as to facilitate theintroduction of the tab into the slot 16 of an underlying shingle. Thetab or locking segment 19 of butt portion 14 similarly is formed with awedge-shaped slot 21a, a throat 22a, a toe or lock section 24a and ahook edge 25a.

The toes with their .hook edges have an important part in the retentionof the tabs in the slots under severe wind conditions. In the drawings,the left tab 18 is shown wider than the right tab 19. This assists ininserting the tabs, for the left tab is inserted first into the slot 16of an underlying'shingle'and may be partially engaged and still leavesulfiicient clearance for the insertion of the right tab into the slot17 of the same underlying shingle. It is important, however, to have thehook edges at a sufiicient distance from the outside edge of the tabs soas to provide enough body to the toe sections to prevent tearing understress, and hence it is un desirable to remove too much from the righttab.

The slot portions 16 and 17 referred to above, and into which areinserted tabs 18 and 19, respectively, of an overlying shingle, areformed by recesses cut inwardly along the upper exposed margins of thebutt portions 13 and 14. The slots extend inwardly about the samedistance as the width of the throat portions of the tabs. The lowerboundaries of the slots may be substantially perpendicular to the edgesof the butt portions. The upper boundaries are spaced a sufiicientdistance from the lower to permit the ready insertion of the tab. It ispreferred that the upper boundariesincline upwardly so as to formtriangular-shaped slots 16 and 17 as shown in the drawing, as this hasbeen found to greatly aid in inserting the tabs.

The shingle units are applied either individually or as a strip to thewooden roof deck in the same manner as for any other square-butt asphaltstrip shingle. The nails are driven about one-half inch above theinnermost point of the slots, as shown at 26 in FIG. 3, and at the freeend in substantially the same line. The latter nail is not absolutelynecessary but desirable- It; is important that the location of the nailswith respect to the slots be close a above if maximum wind resistance isunderlying shingle after it has been nailed down, as shown in FIG. 3.The butt portions of each shingle unit adjacent the slots 16 and 17 maybe raised to aid in introducing the tabs. The shingle is adjusted untilthe tabs are completely inserted under the shingles of the underlyingcourse in which position the throats thereof will coincide substantiallywith the lower portions of the slots and the lower exposed edges of theinserted shingle are substantially in line with the lower edges of theslots of the underlying shingle. This completely conceals the tabs asthey are now under the underlying shingle with parts of the lockingportions, including the toes, extending beyond the throats and the nailsand firmly incased by the butt portions of the shingles of theimmediately underlying course.

It will be found that the tabs are very easily inserted and moved inplace in the direction shown by the arrows in FIG. 3. Considerable ofthis ease in insertion is due to the wide mouths of the wedge-shapedrecesses 21 and 21a and to the wide mouths of the triangular-shapedslots 16 and 17 shown in FIG. 2. Theselatter slots may also be formed bywidely spaced lines parallel with the extreme upper exposed margins ofthe butt portions. However, slots having an angular upper edge aregreatly preferred, for they permit the tabs to slide and turn as theyare drawn through the slots by the action, of the wind upon the buttportions and still the ,slots'provide means which will engage the hookedge of the tabs, thus stopping any further outward movement.

It has been found that the width of the slots 16 and 17 and 21 and 21aalong the cut-out edge or mouth should be at least one-half inch. If theslots 16 and 17 were of this width along the full extent, the nailswould be too far from the point at which the hook edges would beengaged. This, plus the extreme width of the slots throughout theirentire length would not allow the hook edges to be caught in any mannerand the tabs would release completely. On the other hand, whenthe upper4 edges extend upwardly and outwardly at an angle the nail is close tothe hook edges of the tabs as they assume their respective catchpositions, and also the upper edges are in a position where they aremore easily engaged.

It is not advisable, however, to have the upper edges of the recesses 21and 21a intersect the lower edge of the shingle butt portions at anangle greater than 60 degrees; for otherwise there may not beenoughvmaterial between the nail and the slot to prevent tear-out.Arange of between thirty and forty degrees for the angle will be foundquite satisfactory, with thirty degrees preferred. As mentioned-above,the lower range for the angle. is that which will give at least aone-half inch width to the slot at the cut-out.

In forming the angular slots 16 and 17 and 21 and 21a, it will be foundfrom a practical standpoint that a clean acute angle of the upper andlower edge cannot be cutout so it is necessary to curve the intersectionslightly such as with a radius of one-eighth inch.

When the exposed or butt portions are subjected to a wind of extremelyhigh velocity the tabs will slide in the slots, thus permitting thebutts to elevate to a limited degree and turn slightly to the right asshown in FIG. 4 so as to tend to place the throats of the tabs intension rather than in twist. The tabs are much more resistant tofailure by tension than by twist or tear. The tabs are stopped in theirmovement toward the right position of FIG. 4 by the hook edges 25 and25a of the toes 24 and 24a, respectively, being firmly grasped by theshingles in the vicinity of the nails. The nails have firmly placed theshingles of the underlying course against those of the one next lowerone. If the tabs did not permit the shingles to raise slightly bysliding through the slot to the desired position, the tab would bereadily torn off by the wind; also, if the toes on the tabs are absent,the tabs would continue to slide to full release as there is nothing tocatch or book onto the shingles of the next lower course. The tendencyof the tabs to move when the butts are elevated by the wind until theshingle has reached the point where some of the tearing stress isrelieved and then to be held firmly by the hook edge, greatlycontributes to the success of the invention. When the wind subsides, thebutt portions return to the original positions or maybe easily pattedback into place with little damage.

While particular embodiments of the invention have been shown, it willbe understood, of course, that theinventi on is not limited theretosince many modifications may be made, and it is, therefore, contemplatedby the appended claims to cover any such modifications as fall withinthe true spirit and scope of the invention.

The invention having thus been described, what is claimed and desired tobe secured by Letters Patent is:

1. An interlocking square butt type shingle comprising a head portionand a butt portion adapted to be exposed when a plurality of saidshingles are laid in overlapping courses, said butt portion comprisingat least one individual shingle-simulating unit and having a verticallyextending cut-out disposed along one side thereof and extending inwardlyfrom the exposed downward edge of said butt portion substantially itsfull length, a wedge-shaped, wide-mouthed slot extending inwardly from aside of said unit, said slot having a lower edge defined by a lineextending along the extreme upper exposed margin of said butt portionand having an upper edge angularly disposed relative to and spaced fromsaid lower edge, said lower and upper edges joined by a radial terminusat the inward end of said slot; a tab element extending beyond theexposed butt portion ofsuch unit, a wedge-shaped, wide-mouthedrecess'extending into said tab from a side thereof opposite from saidslot to form a throat between the remaining portion of said tab and saidbutt portion, said recess having an upper edge defined by the lowerexposed edge of said butt portion and having alower edge inclinedupwardly and inwardly at anangle' of between :thirty andforty degreeswith said upper edge of said recess to form a radial terminus with saidupper edge at said throat, an outer portion of said inclined edgeextending beyond thereof but spaced from said exposed edge substantiallymore than the thickness of said butt portion to form a toe section, saidtoe section terminating in a hook edge, substantially right-angularlydisposed to said inclined edge and adjacent to but spaced from saidthroat substantially more than the thickness of said butt portion; thewidth of said throat and the lower edge of said slot being ofsubstantially the same dimension.

2. A roof construction comprising a series of courses of interlockingsquare butt type shingles, each of which shingles has a head portion andat least one butt portion adapted to be exposed when a plurality of saidshingles are laid in overlapping course, said butt portion comprising atleast one individual shingle-simulating unit having a verticallyextending cut-out disposed along one side thereof and extending inwardlyfrom the exposed downward edge of said butt portion substantially itsfull length, the butt portions of the shingles of one course overlyingthe head portions of the shingles of the immediately underneath course,each of said units including a wedgeshaped, wide-mouthed slot extendinginwardly from a side of the respective unit, each of said slots having alower edge defined by a line extending along the extreme upper exposedmargin of said butt portion and having an upper edge angularly disposedrelative to and spaced from said lower edge, said lower and upper edgesjoined by a radial terminus at the inward end of said slot; nailspenetrating said shingles adjacent the inner ends of said slots; each ofsaid butt portions including a tab element extending beyond the exposedbutt portion thereof and each of said tabs including a wedge-shaped,wide-mouthed recess extending thereinto and directed oppositely to saidslots to form a throat between the remaining portion of said tab andsaid butt portion, each of said recesses having an upper edge defined bythe lower exposed edge of said butt portion and having a lower edgeinclined upwardly and inwardly at an angle of between thirty and fortydegrees with said upper edge of said recess to form a radial terminuswith said upper edge at said throat, an outer portion of said inclinededge extending beyond thereof but spaced from said exposed edgesubstantially more than the thickness of said butt portion to form a toesection, each of said toe sections terminating in a hook edge,substantially right-angularly disposed to said inclined edge andadjacent to but spaced from said throat substantially more than thethickness of said butt portion, the shingles of each course beingdisposed so that each recess in each tab of each shingle is received inthe cooperating slot of the immediately underlying shingle with each ofsaid locking members disposed in a position to engage the adjacent nailupon raising of the shingle butt portions.

References Cited in the file of this patent UNITED STATES PATENTS1,648,692 McCarthy Nov. 8, 1927 2,452,708 Abraham Nov. 2, 1948 2,598,497Brown et al. May 27, 1952 2,659,322 Abraham Nov. 17, 1953 2,841,099Abraham July 1, 1958 OTHER REFERENCES Roofing & Siding Contractor, May1956, p. 4.

